Modern communications systems increasingly comprise mobile communications devices, in particular mobile voice communications devices. With wireless voice transmission voice signals to be transmitted in real time are usually digitized and transmitted via a radio interface in the form of data packets. Various transmission standards, such as DECT (Digital European Cordless Telecommunications) or GSM (Global System for Mobile Communications) have established themselves in the field of bi-directional wireless voice communication. Furthermore current tendencies can be observed which aim at also using what are known as WLANs (Wireless Local Area Networks) for wireless voice transmission.
Said wireless transmission techniques use transmission frequencies of the order magnitude of up to a few gigahertz. This corresponds to transmission wavelengths of approximately 30 cm and below.